Field of the Disclosure
Various embodiments described herein relate to a method and apparatus that is used to prevent the generation of garbage data after certain parameters associated with the data, such as an encryption parameter, are changed.
Description of the Related Art
Storing data includes writing information representing the data to a storage device or apparatus. There are many types of storage devices. Even though varied, most of the storage devices have common goals. Among the goals are to store increased amounts of data, and to provide a means to make sure the data as stored is secure. Encryption is one way to make the data secure. Encryption is the process of encoding information in such a way that only authorized parties can read it. Encryption doesn't prevent hacking but it reduces the likelihood that the hacker will be able to read the data that is encrypted. In an encryption scheme, the information, referred to as plaintext, is encrypted using an encryption algorithm, turning it into an unreadable ciphertext. This is usually done with the use of an encryption key, which specifies how the message is to be encoded. Any adversary that can see the ciphertext should not be able to determine anything about the original information. An authorized party, however, is able to decode the ciphertext using a decryption algorithm, that usually requires a secret decryption key, that adversaries do not have access to. For technical reasons, an encryption scheme usually needs a key-generation algorithm to randomly produce keys.
From time to time, encryption parameters, such as encryption/decryption keys, can be changed for a storage device. When encryption parameters are changed, like a key or range parameter, it is possible to have garbage data with cyclic redundancy check (“CRC”) errors in the logical block address (“LBA”) space of the change.
Currently, a solution for preventing the CRC errors is to disable all data protection on encrypted drives. This exposes the data. The data is not secure when the data protection scheme is disabled. Of course, this solution falls short of certain standards for the security of the data. Many manufacturers that use storage devices in products they offer qualify the storage devices on the basis of compliance with standards. Turning off the security feature prevents proper T10 data protection on encrypted storage devices. Another standard many have to comply with is the Opal SSC standard. The standard states that:                “The Opal SSC is an implementation profile for Storage Devices built to:                    Protect the confidentiality of stored user data against unauthorized access once it leaves the owner's control (involving a power cycle and subsequent deauthentication)            Enable interoperability between multiple SD vendors                        “An Opal SSC compliant SD:                    Facilitates feature discoverability            Provides some user definable features (e.g. access control, locking ranges, user passwords, etc.)            Supports Opal SSC unique behaviors (e.g. communication, table management) [Section 2.1, page 10/81]                        
If the data is secure at all times, the confidentiality of stored user data is protected against unauthorized access once it leaves the owner's control. In addition, meeting a standard for security of the data on a storage apparatus enables interoperability between multiple storage device vendors. Meeting a standard also facilitates feature discoverability, provides some user definable features (e.g. access control, locking ranges, user passwords, etc.) and supports unique behaviors (e.g. communication, table management).